Method for testing a local number portability (LNP) ported telephone number

ABSTRACT

A method for testing a Local Number Portability (LNP) ported telephone number is provided according to the invention. The method includes in a first switch generating a LNP test telephone call to a second switch. The LNP test telephone call is targeted to the LNP-ported telephone number associated with the first switch. The method further includes indicating that the LNP-ported telephone number is being correctly routed in the second switch if the first switch receives the LNP test telephone call back from the second switch. The method further includes indicating that the LNP-ported telephone number is being incorrectly routed in the second switch if the first switch does not receive the LNP test telephone call back from the second switch.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention is related to the field of Local Number Portability (LNP)capability, and in particular, to a method for testing a LNP-portedtelephone number.

2. Statement of the Problem

Local Number Portability (LNP) is a scheme for allowing persons (and/orinstitutions) to keep an existing telephone number. The LNP capabilityallows a subscriber to keep an existing telephone number even when thesubscriber physically moves or when the subscriber changes telephoneservice providers. The LNP capability enables subscribers to move orchange service providers without the need to inform all potentialcallers of a new telephone number. The LNP process is transparent toboth the caller and the called party.

Before LNP, telephone numbers were assigned to a localservice-provider's end offices on an NPA-NXX basis. An NPA-NXX isdefined as the Numbering Plan Area (NPA) and an office code (NXX) of anend user's telephone number (e.g., 123-456-7890). Each NPA-NXX caninclude up to 10,000 different telephone numbers. In the past, atelephone number identified the person/telephone, as well as the actualend office or telephone switching system that served the person. As aresult, the dialed NPA-NXX was the terminating switch's routing addressto the rest of the network. With the implementation of LNP, which allowsany number of local service providers to serve the same NPA-NXX, thisrouting scheme could no longer be used.

The LNP architecture utilizes a unique 6-digit LRN to identify eachswitch in the network for call routing purposes. Each switch is assigneda LRN. Consequently, a LNP information entry correlates a dialed (i.e.,destination) telephone number to a LRN of a terminating switch. The LRNis used to route the call to the terminating switch, and the originaldialed telephone number is then used by the terminating switch tocomplete the call.

FIG. 1 shows a conventional prior art LNP process, wherein a destinationtelephone number has been ported using the LNP capability. The sourcetelephone initiates a telephone call to the destination telephone bydialing a destination telephone number. The dialed number is received ina local (originating) switch. The originating switch can signal arouting resource, such as a Signal Control Point (SCP), in order toobtain routing information for the destination telephone. Theoriginating switch performs a “LNP dip” and accesses a LNP database orother LNP information. If the dialed number is in the LNP database, thetelephone number has been ported via local number portability. If thedialed number is not in the LNP database, the dialed number is used toroute and connect the telephone call. In this example, the LNP dipproduces a 10 digit number, where a Location Routing Number (LRN) is thefirst 6 digits. Herein the term subLRN refers to the use of all 10digits for routing and connecting the telephone call, rather than usingjust the 6 digit LRN. This 10 digit number is substituted into a Calledparty Number Field (CdPN) of the call signaling, replacing the dialednumber. The dialed number, however, is retained in a Generic AddressParameter (GAP) field of the call signaling for future use. The SCPprovides the LRN and the dialed number back to the originating switch.The originating switch then routes and connects the telephone call tothe terminating switch. The telephone call can transit any number ofintermediate switches. The terminating switch receives the telephonecall, according to the LRN (i.e., the first 6 digits of the called partynumber parameter). The terminating switch recognizes its LRN, retrievesthe original dialed number from the GAP, and connects the telephone callto the destination telephone using the dialed number.

When a LNP dip is not performed for a ported number (e.g., theoriginating switch is not LNP capable) or when the LNP dip fails, thenthe call will be routed based on the originally dialed telephone number.The call will accordingly be routed to the switch from which the numberwas ported. This switch will perform a LNP dip and will route the callbased on the LRN obtained from this LNP dip.

On occasion, a new switch is added to a telephone network. A new switchmay be added for various reasons, including replacement of an existingswitch, upgrading of an existing switch, adding a switch to handleincreased number of subscribers, adding a new switch as an interface toanother network, etc. The addition of a new switch will likely requireassignment of a LRN number to the new switch. In addition, the routinginformation of existing switches will need to be updated in order toproperly route a call that includes the LRN of the new switch. If therouting information for the LRN is incorrect, calls to telephone numbersassigned to the new switch will fail.

SUMMARY OF THE SOLUTION

A method for testing a Local Number Portability (LNP) ported telephonenumber is provided according to the invention. The method comprises in afirst switch generating a LNP test telephone call to a second switch.The LNP test telephone call is targeted to the LNP-ported telephonenumber associated with the first switch. The method further comprisesindicating that the LNP-ported telephone number is being correctlyrouted in the second switch if the first switch receives the LNP testtelephone call back from the second switch. The method further comprisesindicating that the LNP-ported telephone number is being incorrectlyrouted in the second switch if the first switch does not receive the LNPtest telephone call back from the second switch.

A method for testing a LNP-ported telephone number is provided accordingto the invention. The method comprises in a first switch generating aLNP test telephone call to a second switch. The LNP test telephone callis targeted to the LNP-ported telephone number associated with the firstswitch. The method further comprises indicating that the LNP-portedtelephone number is being correctly routed in the second switch if thefirst switch receives the LNP test telephone call back from the secondswitch. The method further comprises in the first switch generating aLRN test telephone call to the second switch if the first switch doesnot receive the LNP test telephone call back from the second switch. TheLRN test telephone call is targeted to the LRN of the first switch. Themethod further comprises indicating that the LRN is being incorrectlyrouted in the second switch if the first switch does not receive the LNPtest telephone call back from the second switch and if the first switchdoes not receive the LRN test telephone call back from the secondswitch. The method further comprises indicating that an LNP dipperformed by the second switch produced an erroneous LRN for the LNPtest telephone call if the first switch does not receive the LNP testtelephone call back from the second switch and if the first switchreceives the LRN test telephone call back from the second switch.

A method for testing a LNP-ported telephone number is provided accordingto the invention. The method comprises disabling a LNP dip capability ina first switch and in the first switch generating a LNP test telephonecall to a third switch through at least a second switch. The LNP testtelephone call is targeted to the LNP-ported telephone number associatedwith the first switch. The method further comprises indicating that theLNP-ported telephone number is being correctly routed in the thirdswitch if the first switch receives the LNP test telephone call backfrom the third switch. The method further comprises indicating that theLNP-ported telephone number is being incorrectly routed in the thirdswitch or in some intermediate switch if the first switch does notreceive the LNP test telephone call back from the third switch.

DESCRIPTION OF THE DRAWINGS

The same reference number represents the same element on all drawings.

FIG. 1 shows a conventional, prior art LNP process, wherein adestination telephone number has been ported using the LNP capability.

FIG. 2 shows a switch environment for testing an assigned LocationRouting Number (LRN) according to an embodiment of the invention.

FIG. 3 is a message flow diagram for the LRN testing of FIG. 2, showingmessages that are generated in the test according to an embodiment ofthe invention.

FIG. 4 is a flowchart of a method for testing an assigned LRN accordingto an embodiment of the invention.

FIG. 5 shows a switch environment for testing a Local Number Portability(LNP) ported telephone number according to an embodiment of theinvention.

FIG. 6 is a message flow diagram for the LNP-ported telephone numbertesting of FIG. 5, showing messages that are generated in the testaccording to an embodiment of the invention.

FIG. 7 is a flowchart of a method for testing a LNP-ported telephonenumber according to an embodiment of the invention.

FIG. 8 is a message flow diagram for the LNP-ported telephone numbertesting of FIG. 5, showing messages that are generated in the testaccording to an embodiment of the invention.

FIG. 9 is a flowchart of a method for testing a LNP-ported telephonenumber according to an embodiment of the invention.

FIG. 10 shows a switch environment for testing a LNP-ported telephonenumber according to an embodiment of the invention.

FIG. 11 is a message flow diagram for the LNP-ported telephone numbertesting of FIG. 10, showing messages that are generated in the testaccording to an embodiment of the invention.

FIG. 12 is a flowchart of a method for testing a LNP-ported telephonenumber according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 2-12 and the following description depict specific examples toteach those skilled in the art how to make and use the best mode of theinvention. For the purpose of teaching inventive principles, someconventional aspects have been simplified or omitted. Those skilled inthe art will appreciate variations from these examples that fall withinthe scope of the invention. Those skilled in the art will appreciatethat the features described below can be combined in various ways toform multiple variations of the invention. As a result, the invention isnot limited to the specific examples described below, but only by theclaims and their equivalents.

FIG. 2 shows a switch environment 100 for testing an assigned LocationRouting Number (LRN) according to an embodiment of the invention.Elements in common share reference numbers. The LRN is assigned to afirst switch 104. The switch environment 100 includes at least the firstswitch 104 and a second switch 106. It should be understood that theswitch environment 100 can include additional switches. The first switch104 is assigned a LRN of 913-555. The second switch 106 includes routinginformation 150 that is used by the second switch 106 to route atelephone call that includes a LRN. The LRN testing in this figure teststhe routing information 150 of the second switch 106 and determines ifthe LRN assigned to the first switch 104 is properly routed by therouting information 150.

In the LRN test, the first switch 104 generates a LRN test telephonecall to the second switch 106. The LRN test telephone call is targetedto the LRN that is assigned to the first switch 104, i.e., the CalledParty Number (CdPN) field of the LRN test telephone call includes the6-digit LRN. The LRN test telephone call is not transmitted to thesecond switch 106 using a telephone number and the LRN test telephonecall does not have to be originated from a telephone. The LRN testtelephone call can be generated by the first switch 104 according toprogramming of the first switch 104 or can be generated by a device incommunication with the first switch 104.

Upon receiving the LRN test telephone call, the second switch 106 willtransfer the LRN test telephone call on to another switch, as the secondswitch 106 is not the destination switch. The second switch 106 willtransfer the LRN test telephone call based on information within thecall signaling of the LRN test telephone call. If the LRN of the firstswitch 104 is correctly programmed into the routing information 150 ofthe second switch 106, then the second switch 106 will route the LRNtest telephone call back to the first switch 104 based on LRN. As aresult, if the LRN test telephone call (and/or call signaling, forexample) is not received back in the first switch 104 within apredetermined time period, then an error must exist within the LRNrouting process in the second switch 106.

Consequently, the test indicates that the LRN is being correctly routedin the second switch 106 if the first switch 104 receives the LRN testtelephone call back from the second switch 106. The test indicates thatthe LRN is being incorrectly routed in the second switch 106 if thefirst switch 104 does not receive the LRN test telephone call back fromthe second switch 106.

The error indication can comprise any manner of error signal, message,record, log, etc. In one embodiment, the LRN testing can be performedfor multiple switches, and error indications can be accumulated orcopied to a central error log that indicates which switches of themultiple switches have incorrect routing information, if any.

FIG. 3 is a message flow diagram for the LRN testing of FIG. 2, showingmessages that are generated in the test according to an embodiment ofthe invention. The first switch 104 generates a LRN test telephone callto the second switch 106. The LRN test telephone call is targeted to theLRN that is assigned to the first switch 104. The second switch 106receives the LRN test telephone call and performs routing based on theLRN included in the LRN test telephone call. Because the LRN testtelephone call already includes an LRN, the second switch 106 does notneed to perform a LNP dip. The second switch 106 consults the routinginformation 150. If the second switch 106 is properly configured, thesecond switch 106 will return the LRN test telephone call to the firstswitch 104. However, if the routing information 150 is not correct, thenthe LRN test telephone call will not be returned to the first switch104. If the first switch 104 receives the LRN test telephone call backfrom the second switch 106, then the test can be determined to besuccessful and the LRN has been correctly routed in the second switch106.

FIG. 4 is a flowchart 400 of a method for testing an assigned LRNaccording to an embodiment of the invention. The LRN is assigned to afirst switch 104. In step 401, the first switch 104 generates a LRN testtelephone call to the second switch 106, with the LRN test telephonecall being targeted to the LRN of the first switch 104, as previouslydiscussed.

In step 402, the first switch 104 waits for the LRN test telephone callto be returned back from the second switch 106. The first switch 104waits for a predetermined time period. If the LRN test telephone call isnot returned from the second switch 106 by the end of the predeterminedtime period, then the method proceeds to step 403. Otherwise, if the LRNtest telephone call is returned from the second switch 106 by the end ofthe predetermined time period, the method exits.

In step 403, because the LRN test telephone call is not returned fromthe second switch 106, an error is indicated.

The LRN testing can additionally be performed in an automated fashion.For example, LRN testing schedules can be transmitted to variousswitches of a communication network. A LRN testing schedule can includetesting information such as an originating switch identifier, a targetedswitch identifier, a testing time when the test is to be performed, andone or more LRNs to be tested. The originating switch can receive thetesting schedule and can perform the LRN testing that is specified inthe testing information.

FIG. 5 shows a switch environment 500 for testing a Local NumberPortability (LNP) ported telephone number according to an embodiment ofthe invention. The switching environment 500 includes a first switch 104and a second switch 106. The second switch 106 has been assigned a LRNof 913-222 in this example, and the first switch 104 has been assigned aLRN of 913-555.

The first switch 104 includes a number of associated telephones andtelephone lines. One such telephone 109 is shown. The telephone 109 hasa telephone number of 913-222-1234. In this example, the telephonenumber 913-222-1234 comprises a LNP-ported telephone number, as thetelephone 109 has been physically moved from the second switch 106 tothe first switch 104. This number is a number that the subscriberdesired to keep, and therefore had ported to the first switch 104 viathe LNP capability. Without the use of the LNP capability, the telephonenumber of the telephone 109 would be 913-555-1234, reflecting the localswitch that is physically connected to the telephone 109. However, whena telephone number is ported, the telephone number of the telephone 109stays the same even when it is moved to a different local switch. As aresult, in the example shown the telephone number remains 913-222-1234.

In an example of proper LNP operation of the LNP-ported telephonenumber, the first switch 104 generates a LNP test telephone call to thesecond switch 106 using the LNP-ported telephone number of 913-222-1234.The second switch 106 performs a LNP dip 122 in order to route the LNPtest telephone call. The LNP dip 122 correlates the dialed telephonenumber to a stored LRN, wherein the LRN is a 6-digit number thatspecifies an end (i.e., local) switch. The LNP dip 122 accesses the LRNfrom a LNP database 120. In one embodiment, the LRN informationcomprises a LRN table 130 that stores LNP-ported telephone numbers andcorresponding LRNs. In this example of proper LNP operation, the inputLNP test telephone call of 913-222-1234 produces the LRN of 913-555. TheLRN is substituted into the CdPN field and the LNP test telephone callis then routed from the second switch 106 based on the CdPN field. Thesecond switch 106 therefore uses the LNP dip response 124 to route theLNP test telephone call back to the first switch 104, using a routinginformation 150 of the second switch 106.

In certain situations or scenarios, it is greatly desired to test theLRN-ported telephone number of the telephone 109. For example, if thefirst switch 104 has been modified, testing may be needed. If thetelephone 109 has just been ported (i.e., has just been assigned a newLRN number), then testing may be needed. Other testing scenarios mayalso exist.

To test the LNP-ported telephone number, the first switch 104 generatesa LNP test telephone call to the second switch 106. The LNP testtelephone call is targeted to the LNP-ported telephone number, i.e., theCdPN from the first switch 104 comprises the telephone number913-222-1234. The LNP test telephone call is transferred to the secondswitch 106 by the first switch 104 and the first switch 104 waits forthe LNP test telephone call to be returned. If the routing information150 of the second switch 106 is correct, then the routing of the LNPtest telephone call in the second switch 106 will return the LNP testtelephone call back to the first switch 104. If the first switch 104receives the LNP test telephone call back from the second switch 106,then the LNP-ported telephone number is fully functional and the routingin the second switch 106 is correct. All LNP-ported telephone numbers ofthe first switch 104 (or any switch) can be tested in this manner, suchas in an iterative fashion.

If the first switch 104 does not receive the LNP test telephone callback, then two separate problems may exist. A first possible problem isthat the LNP-ported telephone number may be improperly stored in the LNPdatabase 120. As a result, a LNP dip process may retrieve an incorrectLRN and insert the incorrect LRN in the LNP test telephone call. Theincorrect LRN will result in erroneous routing. A second possibleproblem is that a correct LRN obtained from the LNP database 120 may beimproperly routed in the second switch 106. For example, routinginformation 150 of the second switch 106 may be erroneous, and thesecond switch 106 may route the LNP test telephone call improperly evenif the LRN retrieved for the telephone call is correct.

The test of FIG. 5 does not indicate which problem may have occurred.The test of FIG. 5 only shows that one (or maybe both) error conditionsare present. However, the test of FIG. 5 may be used in conjunction withother test routines in order to fully determine a source of error (seeFIGS. 8-9 and the accompanying discussion below).

FIG. 6 is a message flow diagram for the LNP-ported telephone numbertesting of FIG. 5, showing messages that are generated in the testaccording to an embodiment of the invention. The first switch 104generates a LNP test telephone call to the second switch 106. The LNPtest telephone call is targeted to the LNP-ported telephone numberassociated with the first switch 104. The second switch 106 receives theLNP test telephone call and determines that the included telephonenumber is a LNP-ported telephone number. Subsequently, the second switch106 generates a LNP dip 122 to the LNP database 120 in order to obtain acorresponding LRN. The LNP dip response 124 provides a LRN to the secondswitch 105. The second switch 106 routes the LNP test telephone call tothe LRN that is obtained through the LNP dip 122. If the LNP dip 122obtains the correct LRN and if the second switch 106 has correct routinginformation 150, then the LNP test telephone call will be returned tothe first switch 104. However, if the routing in the second switch 106is not correct, then the LNP test telephone call will not be returned tothe first switch 104. If the first switch 104 receives the LNP testtelephone call back from the second switch 106, then the test can bedetermined to be successful and the LRN has been correctly routed in thesecond switch 106. If the first switch 104 does not receive the LNP testcall back from the second switch 106, the first switch 104 can indicatethat the LNP-ported telephone number is being incorrectly routed in thesecond switch 106.

FIG. 7 is a flowchart 700 of a method for testing a LNP-ported telephonenumber according to an embodiment of the invention. In step 701, thefirst switch 104 generates a LNP test telephone call to the secondswitch 106, with the LNP test telephone call being targeted to theLNP-ported telephone number associated with the first switch 104, aspreviously discussed.

In step 702, the first switch 104 waits for the LNP test telephone callto be returned back from the second switch 106. The first switch 104waits for a predetermined time period. If the LNP test telephone call isnot returned from the second switch 106 by the end of the predeterminedtime period, then the method proceeds to step 703. Otherwise, if the LNPtest telephone call is returned from the second switch 106 by the end ofthe predetermined time period, the method exits.

In step 703, because the LNP test telephone call is not returned fromthe second switch 106, an error is indicated. The error indicates thatthe LNP-ported telephone number is not being correctly routed in thesecond switch 106.

The LNP testing can additionally be performed in an automated fashion.For example, LNP testing schedules can be transmitted to variousswitches of a communication network. A LNP testing schedule can includetesting information such as an originating switch identifier, a targetedswitch identifier, a testing time when the test is to be performed, andone or more LNP-ported telephone numbers to be tested. The originatingswitch can receive the testing schedule and can perform the LNP testingthat is specified in the testing information.

FIG. 8 is a message flow diagram for the LNP-ported telephone numbertesting of FIG. 5, showing messages that are generated in the testaccording to an embodiment of the invention. The first switch 104generates a LNP test telephone call to the second switch 106. The LNPtest telephone call is targeted to the LNP-ported telephone numberassociated with the first switch 104. The second switch 106 receives theLNP test telephone call and determines that the included telephonenumber is a LNP-ported telephone number. Subsequently, the second switch106 can generate a LNP dip 122 to the LNP database 120 in order toobtain a corresponding LRN. A LNP dip response 124, if received,provides a LRN to the second switch 105. In this example, the LNP testtelephone call is not returned to the first switch 104 (i.e., the“Returned?” box does not receive signaling back from the second switchin response to the LNP test telephone call). At this point, the firstswitch 104 cannot determine the cause of the lack of the returned LNPtest telephone call. Therefore, a LRN test can optionally be conductedin order to obtain more information and determine why the LNP testtelephone call failed. The following steps are optional, and may beunnecessary wherein STP test capabilities exist to track the LNP testtelephone call or otherwise log any resulting activities of the affectedswitch(es) or components.

As a consequence, the first switch 104 generates a LRN test telephonecall to the second switch 106. The LRN test telephone call is targetedto the LRN of the first switch 104. If the first switch 104 receives theLRN test telephone call back from the second switch 106, then the LRNhas been correctly routed in the second switch 106. The error can thenbe determined to be an error in the LNP dip, including erroneousinformation in the LNP database 120.

If the first switch 104 does not receive the LRN test telephone callback from the second switch 106, then the LRN routing in the secondswitch 106 is erroneous and the error can be determined to be in therouting information 150.

FIG. 9 is a flowchart 900 of a method for testing a LNP-ported telephonenumber according to an embodiment of the invention. In step 901, thefirst switch 104 generates a LNP test telephone call to the secondswitch 106, with the LNP test telephone call being targeted to theLNP-ported telephone number associated with the first switch 104, aspreviously discussed.

In step 902, the first switch 104 waits for the LNP test telephone callto be returned back from the second switch 106. The first switch 104waits for a predetermined time period. If the LNP test telephone call isnot returned from the second switch 106, then the method proceeds tostep 903. Otherwise, if the LNP test telephone call is returned from thesecond switch 106, the method exits.

In step 903, the first switch 104 generates a LRN test telephone call tothe second switch 106, with the LRN test telephone call being targetedto the LRN of the first switch 104, as previously discussed.

In step 904, the first switch 104 waits for the LRN test telephone callto be returned back from the second switch 106. The first switch 104waits for a predetermined time period. If the LRN test telephone call isreturned by the end of the predetermined time period, then the methodbranches to step 905. Otherwise, if the LRN test telephone call is notreturned by the end of the predetermined time period, the methodbranches to step 906.

In step 905, because the LRN test telephone call is returned from thesecond switch 106, a LNP dip error is indicated.

In step 906, because the LRN test telephone call is not returned fromthe second switch, a LRN routing error is indicated. The LRN routingerror is due to an error in the routing information 150 of the secondswitch 150. The LRN routing error can be in the second switch.Alternatively, the LRN routing error can be an error in an intermediateswitch.

It should be understood that this method comprises both a LNP test and aLRN test. Although the LNP test is shown as being performed first,alternatively the method could perform the LRN test before the LNP test.

The LNP testing can be performed in an automated fashion. For example,LNP testing schedules can be transmitted to various switches of acommunication network. A LNP testing schedule can include testinginformation such as an originating switch identifier, a targeted switchidentifier, a testing time when the test is to be performed, one or moreLNP-ported telephone numbers to be tested, and one or more LRNs to betested. The originating switch can receive the testing schedule and canperform the LNP/LRN testing that is specified in the testinginformation.

FIG. 10 shows a switch environment 1000 for testing a LNP-portedtelephone number according to an embodiment of the invention. The switchenvironment 1000 includes a first switch 104. The switch environment1000 also includes neighboring switches 107B-107E. The first switch 104is connected to one or more of the neighboring switches 107B-107E. Theswitch environment 1000 further includes distant switches 108F-108G. Thedistant switches 108F-108G are connected to one or more of theneighboring switches 107B-107E.

Where it is desired to test a LNP function in a distant switch 108F or108G, the originating switch 104 cannot be allowed to perform the LNPdip. It is desired that the distant switch 108F or 108G perform the LNPdip. Therefore, when testing switches beyond the neighboring switches107E or 107D, the originating switch 104 must have its LNP dipcapability disabled. In this manner, it can be ensured that the distantswitch 108F or 108G will perform the LNP dip.

FIG. 11 is a message flow diagram for the LNP-ported telephone numbertesting of FIG. 10, showing messages that are generated in the testaccording to an embodiment of the invention. The LNP dip capability ofthe first switch is first disabled, as previously discussed. The firstswitch 104 generates a LNP test telephone call to a distant switch 108Gthrough a neighboring switch(es) 107. The LNP test telephone call istargeted to a LNP-ported telephone number. The NPA-NXX portion of theLNP test telephone call is associated with the distant switch 108G. Theneighboring switch 107 transfers the LNP test telephone call to thedistant switch 108G. The distant switch 108G therefore performs the LNPdip to an associated LNP database 120. The distant switch 108G receivesa LNP dip response, including a LRN for the first switch 104. Thedistant switch 108G should return the LNP test telephone call to thefirst switch 104 through the neighboring switch(es) 107 if the LNP dipfunctioned correctly (assuming no error in the LRN routing in theneighboring switch(es) 107 and no problem in LRN routing in the distantswitch 108G).

If the LNP dip obtains the correct LRN and the routing information asdiscussed above is correct, then the LNP test telephone call will bereturned to the first switch 104. However, if the LNP dip does notobtain the correct LRN, then the LNP test telephone call will not bereturned to the first switch 104. If the first switch 104 receives theLNP test telephone call back from the distant switch 108G, then the testcan be determined to be successful and that the LNP dip at the distantswitch 108G has been correctly performed and the routing information onthe distant switch and intermediate switches is correct. If the firstswitch 104 does not receive the LNP test telephone call back from thedistant switch 108G, then the first switch 104 can indicate that arouting error has occurred in the distant switch 108G or in anintermediate switch. Existing STP testing capabilities can be used todetermine where the call failed.

FIG. 12 is a flowchart 1200 of a method for testing a LNP-portedtelephone number according to an embodiment of the invention. In step1201, the first switch 104 generates a LNP test telephone call to thedistant switch 108G, with the LNP test telephone call being targeted toa LNP-ported telephone number associated with the first switch 104, aspreviously discussed.

In step 1202, the first switch 104 waits for the LNP test telephone callto be returned back from the distant switch 108G. The first switch 104waits for a predetermined time period. If the LNP test telephone call isnot returned from the distant switch 108G by the end of thepredetermined time period, then the method proceeds to step 1203.Otherwise, if the LNP test telephone call is returned from the distantswitch 108G by the end of the predetermined time period, the methodexits.

In step 1203, because the LNP test telephone call is not returned fromthe distant switch 108G, an error is indicated. The error indicates thatthe LNP-ported telephone number is not being correctly routed. Therouting error can be in the distant switch 108G. Alternatively, therouting error can be in at least one intermediate switch. It should benoted that the testing can be systematically performed, wherein theintermediate switches are tested before the distant switch 108G istested. Consequently, where such systematic testing has been performed,in this step the routing error can be assigned to the distant switch108G.

The LNP testing can be performed in an automated fashion. For example,LNP testing schedules can be transmitted to various switches of acommunication network. A LNP testing schedule can include testinginformation such as an originating switch identifier, a targeted switchidentifier, a testing time when the test is to be performed, and one ormore LNP-ported telephone numbers to be tested. In addition, the testingschedule can include information for disabling LNP dips by specificswitches or nodes. The originating switch can receive the testingschedule and can perform the testing that is specified in the testinginformation.

It should be understood that a test according to any of the embodimentsof the invention can be iteratively performed. A test can be repeatedfor multiple LNP-ported telephone numbers. A test can be repeated forall switches connected to a first switch. A test can be repeatedlyperformed for multiple distant switches.

1. A method for testing a Local Number Portability (LNP) portedtelephone number, the method comprising: in a first switch, generating aLNP test telephone call to a second switch, with the LNP test telephonecall being targeted to the LNP-ported telephone number associated withthe first switch; indicating that the LNP-ported telephone number isbeing correctly routed in the second switch if the first switch receivesthe LNP test telephone call back from the second switch; and indicatingthat the LNP-ported telephone number is being incorrectly routed in thesecond switch if the first switch does not receive the LNP testtelephone call back from the second switch.
 2. The method of claim 1,further comprising waiting a predetermined time period after generatingthe LNP test telephone call before either indicating step.
 3. The methodof claim 1, with a Called Party Number (CdPN) field of a telephone callsignaling for the LNP test telephone call including the LNP-portedtelephone number.
 4. The method of claim 1, with indicating that theLNP-ported telephone number is being incorrectly routed in the secondswitch comprising indicating an error in a LNP dip performed by thesecond switch.
 5. The method of claim 1, further comprising iterativelytesting one or more second switches using one or more subsequent LNPtest telephone calls.
 6. The method of claim 1, further comprisingiteratively testing successive levels of switches inwardly or outwardlyfrom the first switch.
 7. The method of claim 1, further comprising inthe second switch performing an LNP dip to a LNP database and obtainingthe LRN in response to the second switch receiving the LNP testtelephone call.
 8. The method of claim 1, with the indicating that theLNP-ported telephone number is being incorrectly routed in the secondswitch comprising: in the first switch, generating a LRN test telephonecall to the second switch if the first switch does not receive the LNPtest telephone call back from the second switch, with the LRN testtelephone call being targeted to the LRN of the first switch; indicatingthat the LRN is being incorrectly routed in the second switch if thefirst switch does not receive the LNP test telephone call back from thesecond switch and if the first switch does not receive the LRN testtelephone call back from the second switch; and indicating that an LNPdip performed by the second switch produced an erroneous LRN for the LNPtest telephone call if the first switch does not receive the LNP testtelephone call back from the second switch and if the first switchreceives the LRN test telephone call back from the second switch.
 9. Themethod of claim 8, with a Called Party Number (CdPN) field of atelephone call signaling for the LRN test telephone call including theLRN assigned to the first switch.
 10. The method of claim 8, withindicating that the LRN is being incorrectly routed in the second switchcomprising indicating an error in a routing information of the secondswitch.
 11. A method for testing a Local Number Portability (LNP) portedtelephone number, the method comprising: in a first switch, generating aLNP test telephone call to a second switch, with the LNP test telephonecall being targeted to the LNP-ported telephone number associated withthe first switch; indicating that the LNP-ported telephone number isbeing correctly routed in the second switch if the first switch receivesthe LNP test telephone call back from the second switch; in the firstswitch, generating a LRN test telephone call to the second switch if thefirst switch does not receive the LNP test telephone call back from thesecond switch, with the LRN test telephone call being targeted to theLRN of the first switch; indicating that the LRN is being incorrectlyrouted in the second switch if the first switch does not receive the LNPtest telephone call back from the second switch and if the first switchdoes not receive the LRN test telephone call back from the secondswitch; and indicating that an LNP dip performed by the second switchproduced an erroneous LRN for the LNP test telephone call if the firstswitch does not receive the LNP test telephone call back from the secondswitch and if the first switch receives the LRN test telephone call backfrom the second switch.
 12. The method of claim 11, further comprisingin the second switch performing an LNP dip to a LNP database andobtaining the LRN in response to the second switch receiving the LNPtest telephone call.
 13. The method of claim 11, further comprising:waiting a first predetermined time period after generating the LNP testtelephone call before indicating that the LNP-ported telephone number isbeing correctly routed in the second switch; and waiting a secondpredetermined time period after generating the LRN test telephone callbefore indicating that the LRN is being incorrectly routed or beforeindicating that the LNP dip produced an erroneous LRN.
 14. The method ofclaim 11, with a Called Party Number (CdPN) field of a telephone callsignaling for the LNP test telephone call including the LNP-portedtelephone number.
 15. The method of claim 11, with a Called Party Number(CdPN) field of a telephone call signaling for the LRN test telephonecall including the LRN assigned to the first switch.
 16. The method ofclaim 11, with indicating that the LRN is being incorrectly routed inthe second switch comprising indicating an error in a routinginformation of the second switch.
 17. The method of claim 11, furthercomprising iteratively testing one or more second switches using one ormore subsequent LNP test telephone calls and corresponding LRN testtelephone calls.
 18. The method of claim 11, further comprisingiteratively testing successive levels of switches inwardly or outwardlyfrom the first switch.
 19. A method for testing a Local NumberPortability (LNP) ported telephone number, the method comprising:disabling a LNP dip capability in a first switch; in the first switch,generating a LNP test telephone call to a third switch through at leasta second switch, with the LNP test telephone call being targeted to theLNP-ported telephone number associated with the first switch; indicatingthat the LNP-ported telephone number is being correctly routed in thethird switch if the first switch receives the LNP test telephone callback from the third switch; and indicating that the LNP-ported telephonenumber is being incorrectly routed in the third switch or in anintermediate switch if the first switch does not receive the LNP testtelephone call back from the third switch.
 20. The method of claim 19,further comprising waiting a predetermined time period after generatingthe LNP test telephone call before either indicating step.
 21. Themethod of claim 19, with a Called Party Number (CdPN) field of atelephone call signaling for the LNP test telephone call including theLNP-ported telephone number.
 22. The method of claim 19, furthercomprising iteratively testing one or more third switches using one ormore subsequent LNP test telephone calls.
 23. The method of claim 19,further comprising iteratively testing successive levels of switchesinwardly or outwardly from the first switch.
 24. The method of claim 19,with the indicating that the LNP-ported telephone number is beingincorrectly routed in the third switch comprising: in the first switch,generating a LRN test telephone call to the third switch if the firstswitch does not receive the LNP test telephone call back from the thirdswitch, with the LRN test telephone call being targeted to the LRN ofthe first switch; indicating that the LRN is being incorrectly routed inthe third switch if the first switch does not receive the LNP testtelephone call back from the third switch and if the first switch doesnot receive the LRN test telephone call back from the third switch; andindicating that an LNP dip performed by the third switch produced anerroneous LRN for the LNP test telephone call if the first switch doesnot receive the LNP test telephone call back from the third switch andif the first switch receives the LRN test telephone call back from thethird switch.
 25. The method of claim 24, with a Called Party Number(CdPN) field of a telephone call signaling for the LRN test telephonecall including the LRN assigned to the first switch.
 26. The method ofclaim 24, with indicating that the LRN is being incorrectly routed inthe third switch comprising indicating an error in a routing informationof the third switch.
 27. The method of claim 24, further comprising inthe third switch performing the LNP dip to a LNP database and obtainingthe LRN in response to the third switch receiving the LNP test telephonecall.
 28. The method of claim 24, further comprising waiting a secondpredetermined time period after generating the LRN test telephone callbefore either indicating step.